Electric-heating apparatus.



H. L'Q'F UIST. ELECTRIC HEATING APPARATUS.

2 SHEETSSHEET l.

' Patented Dec. 26, 1911.

APPLICATION TILED MARJA, 1910.

INVENTQR.

H. L'O'P UIsT. ELECTRIC HEATING APPARATUS.

APPLICATION FILED MAR. 4, 1910 2 sngmswnnm 2.

K 0 NW E NTOR 4' 2 E PB I I An} 55 ,H w n /g2) Z5? 2% g 22;?

Patented Dec. 26, 1911.

W I N E55 ES rfi fi wawazm gunman. LoFQUIs r, or s'iocxnonm, SWEDEN.

.ruaawhmam wmm;

Be it known that I, HJALHAR Lorouis'r, subject of'the King. of Sweden,residing at .t 43 Artillerigatau, Stockholm,- Sweden, have 5 inventednewand useful Improvementsin.

' Electric-Heating Apparatus, of which the following is a specification.

The present invention relates to electric I fheatin'g' apparatus, andhas for its objectto vprovide such an apparatus, which will communicatea more even and comfortable heat to the rooms, in which it is placed,and; which in the same time will utilize the elec tric energy suppliedin a moreeconomical way than heretofore. Foraccomplishing the saidobjects, the apparatus is so constructed, that the heating coils areinclosd in a special casing, the walls of which are 'madeof steatite(soap-stone),and als o provided'with a device operated by;a contactthermometer for automatically breaking the jcurrent as soon as a-certaindesired temperature'is obtained inzthe apparatus or stove. In aprefferredl-form of the apparatus, the heating coilsiaregal'so wound oncoresaof steatite,

fthismateri'al being known also as a good electric insulator; Ithas alsobeen proved byactual tests, that the steatite issuperior to mostother.materials concerning its ca- 80 pacityof storing large-quantitiesof-"heat and sl'qwly'deliverin the 'same'. For in stance, the saidsteatlte or soap-stone will kep the heat for about twice'the time asordinary fire-brick. The circuit breaking device operated by the contactthermometeris preferably of such a design," that it will continue'tok'ee the circuit broken after breaking it, unti the same circuit isagain closed by hand. In the accompanying drawing, an electric heatingapparatus embodying the invention is illustrat Figure 1 shows the"apparatus in a. rear.

view, partly section,-F1g. 2"the sanle in a plan view-with part of thetop piece broken .away, Fig.;3 thesaid apparatusin'a side. view and Fig.4 a diagram: of connections.

In the example shown thefcasingo'f the apparatus .comprises'a bottompiece 1, rest- 5 ing on wheels or rollers *2, four side walls 3, made intwo .pieces'each, and-a to piece 4,

connected to the b'ottom piece 1 y .means of'clamping screws-5. Thepieces 1, 3- and i are all made of-steatite (soapstone) and providedatthe joints with-ribs 6 engaging grooves in the adjacent parts. ThejointsnLncrnrc-nnnrme nrrimarus.

Specification of Letters Patent. Application filed lil'arcli 4,1910,Se'rial No. 547,381.

Patented nect zfiyieii.

between the upper and lowe partsoffthe side walls-are preferably, butnot 114206 sar ly, covered by a binding metal rim 7, which maybeprovidedwith handles 8. so

The bottom piece 1 is provided with shallow recess'es,'in the exampleshown six in number, for the insertion of a correspondmg number ofsteatite cores 9 for the heat-' ing resistance coils 10. The said coresare .65

provided with spiral grooves 11 for the coils and preferably somewhattapered upward so as to'prevent the'deformation or falling down of thewire'constituting the coil, even when the'same is elongated by theaction-.70 of heat. At their'upper ends, the .co'res.9 I engagerecesse's in asteatite -slab 12 for the purpose of keeping the cores inplace, which is placed at some distance fromthe top iece 4 for leavingspaces forsignal lamps ere- 7-5 after referredtoandalso hascomparatively narrow clearances aces between itself and the side walls3. Rt least two of the-said f side. walls are provided, near theirupperand lower edges, withholes or ports-l3ffor thefcirculat-ion ofairthrough the apparatus] Between the slab 12 and the top piece 4 areinserted a pair of small incandescent 1am s 14 secured to the former andconnected in parallel totheche ating resistance wires for 8a indicatingwhen current is flowing through the latter.- j

The device for automatically-breakingthe current when a certainpredetermined tom-- pe'rature is reached in the' apparatus' comf prisesa contact thermometergfmmd a Iner- .cury:circuit-breakerv comprisln 'acoil :16 ,and an armature17 carrying a glass-tube l8 containingmercury19 and providedwith contact wires 20. .The tubel8=is by igravity'normally held in'suq ap6sition,.thatthe mercury.;w-ill1 cover the endsof both the contact wires 20, but when the coil 16' is energized, itwill lift the armature-together "with the glass-tube to the positionshown in Ifig. 1, in'LWIiichQactiQn the coil may, if-des1red,,be'.assisted bya spring "21.- In the "last -me n'tioned, elevatedposition of the glass-tube, the mercury covers only one of the contactwires. 20. This position of the armature'li' andxthe glass-tube 18 isthen maintained by'means-of a latch 22 engaging beneath a projection 23of the armature 17.

The downward movement of the projection a 23 is possible by reason ofthe fact that'the 11cc lower surface of. the latch 22 is tapered-orrounded off, 'from which it will be undera spindle 25 against the actionof springs 26, 27 so as to release the armature 17, which will then droptogether with the tube 18 to its normal position.

"The electrical connections between the different parts of the apparatusare clearly shown in Fig. 4:. From the positive main 28 the currentpasses through the one pole ofthe: contact plug 29 (shown also in Figs.1 and 2) to the main switch 30 (Figs. 1, a).

'20- Behind this switch it is divided into two portions, the greater ormain portion passing to the heating apparatus proper, where it is againdivided into a main portion through the heating coils 10 and a smallerportion through the lamps 14. After passing through the coils and lampsthese two current portions-are again united to flow through thecontactwires 20 and the mercury 19 of the circuit breaker and thenthrough the other pole of the contact plug 29 to the negative main 3 Thesmaller portion of current branched o'ii immedi-. ately behind theswitch '30 traverses a shu t resistance coil 32 and then joins the. 35main current before thelatter again reaches the two-pole plug 29. From acertain-. part of'the .-'coil 32 a current is branched on", which passesthrough the contact thermometer l5 and the coil 16 and is joined again40 to'the main current before the latter has passed the circuit-breakingtube 17, so that the current through the coil 16 is brokensimultaneously with the main current. The upper contact wire of thethermometer 15 is placed at aheight corresponding to the highesttemperature allowed in the apparatus. When this temperature'is reached,the mercury of the thermometer closes the current throughthe coil 16,which will attract its armature, so that the mercury of the tube 17leaves o i1e of the contact wires 20. Thus, the main current is broken,and the apparatus is left' to cool slowly, communicating a comfortableheat to the surrounding' room. As theicurrent through the coil f 16 issimultaneously broken, the armature would, however,] drop again, if

' the-latch 22 had not been; ngagedbeneath the projection 23L' .No"w,,armature will remaih in itsuppen; ciroui -brea'king position, until itreleased by hand, for ifn stance when the oo'mrequires to be hea dagain.

The

hematite- &5 is provided, in

66 preferred construction, with comparatively wide contact bands 33connected to the wires, which make "contact with the mercury column ofthe thermometer. These bands are adapted to make good contact againstouter bands 34 secured .to' the wall of the apparatus, when thethermometer is put in place. Hereby the" thermometer is also made easilyinterchangeable if less or more heat is wanted. The switch 30, the.

resistance coil 32 and thecircuit-breaking device are arranged indifferent compart-.

ments of a box 35 secured to the rear side of the heating apparatus andprovided with a cover 36 (not shown in Fig. 1) for facilitating themovement of thecomplete stove from one room or place to another. Theconnections between the box 35 and the stove or apparatus proper areeffected by means of flexible two-wire conductors 37,38.

Having now particularly described and ascertained the nature of my saidinvention, and in ,what manner the same is ,to be performed"l ,declarethat what I claim is 1. An {heating apparatus to rooms, coifip'risingheating resistance e ments, w'a s of steatite surrounding saidelements," said walls being provided with-j,

holes for-the 'circulation of air throughthe apparatus contactthermometer inside said walls, aci icuit-breaking device operated bysaid contact thermometer so as to break the" current, through theheating resistance elements when the temperature in the apparatus hasreached a predeterminedjj degree,

and latch means for keeping said"circu1t-.'

breaker device in breaking position until restored to closing positionby hand.

2. An "electric heating apparatus for rooms, comprising heatingresistance ele ments, walls of steatite surrounding said elements, saidwalls being provided .with

holes for the circulation of 'air through-the apparatus a contactthermometer with surrounding contact bands connected to the contacts orwires opcratedby the mercury column, said contact bands being adapted toslide into outer bandseor contacts arranged inside said steatite walls,said outer bands or contacts being connected to the beating resistanceelements and to a circuit-break-- ing device, and latch means forkeeping said circuit-breaking device in breaking position untilvrestored to closing position. by hand. i

3. An electric heating apparatus I for rooms, comprising heatingresistance ele- I current through the heating resistance elements whenthe temperature in the apparatus has reached a predetermined degree,

spindle for moving the lever so as to cause said devicegomprising a coiland an arinaname to this specification in the presence of ture carrying.contacts, a lever With a latch two subscribing witnesses.

catching the end of said armature when I attracted by the coil, and aspring-actuated 'R Y Witnesses BIRGER NORDFELDT, HEDWIG MELINDER.

the latch to re1ea ethe armature.

In testimonyj'whereof I have signed my

